Choose one to be the master catalog and merge the other two using the Import from Another Catalog feature.
Or you could create a new blank catalog and merge them all in using the Import from another Catalog feature if you want to avoid any clutter in your existing catalogs.
Try this tutorial on the exact subject by Kost:
I watched this video, it was great, but what if I'm the unfortunate DOLT that used the same photos in multipule cataloges and only some had edits? How do I contend with THAT issue?
You can find edited photos using a smart collection. So open a catalogue and create a smart collection biased on Has Adjustments and/or Edit Time. This will detect edited photos and allow you to find which ones should go into the new master catalogue. When sure, do an Export as Catalog for these items and import it into the new master. Repeat until done. So essentially I'm saying sort out in each catalogue which images should be in the final one.
Alternatively, decide which catalogue is the LEAST up-to-date, and just import the other catalogues into it. This combined catalogue will now contain the updated versions of the images. Keep the two old catalogues , just in case.
And backup everything before doing anything.
When you import one catalog into another, Lightroom will identify duplicate files and give you options as to how you want those duplicates handled. One of the options allows you to import the dupes (i.e. the same file, not a second copy) but create a virtual copy of the originals so that you can later compare the two sets of edits and decide which one you want to keep.
Possibly, John. I guess a lot would depend upon the extent of the duplication, and more importantly how many have duplicate (different) edits in the two catalogs. IIRC, importing an unedited file into a catalog which already has that file will result in the unedited file being ignored. Doing all the sorting out prior to running the catalog import as per your suggestion would eliminate much confusion. However, the point is that when running the "Import from Another Catalog" that "Changed Existing Photos" box WILL be reported, so it would be as well for the user to be aware....of course "Don't Import New Photos" is one of the options, which I guess would be your recommendation provided it is certain that the "older" edits are in the catlog being imported.
Thanks to both of you for your help, I did find the files I was looking for, thankfully I only had to look through 50,000 files . My question now is, before I export this cataloge of edits I creatid using Smart Collection, how should I name it? Will it be exported as a Catalogue or as a Smart Collection? Or should I give it an arbitrary name and merge it with my master catalog? Thanks again for the help, I'm self taught on Lightroom, whach has created some obvious bad habits that I need to break.
You guys ROCK! Tried your method John, worked like a charm, got all the edits I needed, Master Catalog is up to date, or as much as it needs to be, now I can get back to something a little more productive, like selecting photos for my website! Thanks again.
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